Emerging henipaviruses and flying foxes - Conservation and management perspectives

Wildlife populations are affected by a series of emerging diseases, some of which pose a significant threat to their conservation. They can also be reservoirs of pathogens that threaten domestic animal and human health. In this paper, we review the ecology of two viruses that have caused significant disease in domestic animals and humans and are carried by wild fruit bats in Asia and Australia. The first, Hendra virus, has caused disease in horses and/or humans in Australia every five years since it first emerged in 1994. Nipah virus has caused a major outbreak of disease in pigs and humans in Malaysia in the late 1990s and has also caused human mortalities in Bangladesh annually since 2001. Increased knowledge of fruit bat population dynamics and disease ecology will help improve our understanding of processes driving the emergence of diseases from bats. For this, a transdisciplinary approach is required to develop appropriate host management strategies that both maximise the conservation of bat populations as well as minimise the risk of disease outbreaks in domestic animals and humans. (c) 2006 Elsevier Ltd. All rights reserved.

Pathotypes and serogroups of enterotoxigenic Escherichia coli isolated from pre-weaning pigs in north Vietnam

The contribution of enterotoxigenic Escherichia coli (ETEC) to pre-weaning diarrhoea was investigated over a 6 month period at five selected commercial piggeries (CPs) in north Vietnam with at least 100 sows each. Diarrhoea was found to affect 71(.)5% of the litters born during the period of study. Of 406 faecal specimens submitted for bacteriological culture, 200 (49(.)3%) yielded a heavy pure culture of E coli and 126(31 %)were confirmed by PCR to carry at least one of eight porcine ETEC virulence genes. ETEC was responsible for 43% of cases of diarrhoea in neonatal pigs during the first 4 days of life and 23(.)9% of the remaining cases up until the age of weaning. Pathotypes were determined by PCR for the 126 ETEC isolates together with 44 ETEC isolates obtained from village pigs (VPs) raised by smallholder farmers. The CP isolates belonged to five pathotypes, four of which were also identified in VP isolates. Haemolytic serogroup O149: K91 isolates that belonged to F4/STa/STb/LT were most commonly identified in both CPs (33 % of isolates) and VPs (45(.)5%). Other combinations identified in both production systems included O64 (F5/STa), O101 (F4/STa/STb) and O-nontypable (F-/STb). A high proportion of CP isolates (22(.)3 %) possessed all three enterotoxins (STa/STWLT), lacked the genes for all five tested fimbriae (F4, F5, F6, F41 and F18) and belonged to serogroup O8. These unusual 08 F- isolates were haemolytic and were isolated from all ages of diarrhoeic piglets at each CP, suggesting that they have pathogenic potential.

Responses in carcass lean pH at 24 hours post-mortem in lines of Large White pigs selected for growth rate on a fixed ration over a set time

A restricted maximum likelihood analysis applied to an animal model showed no significant differences (P > 0.05) in pH value of the longissimus dorsi measured at 24 h post-mortem (pH24) between high and low lines of Large White pigs selected over 4 years for post-weaning growth rate on restricted feeding. Genetic and phenotypic correlations between pH24 and production and carcass traits were estimated using all performance testing records combined with the pH24 measurements (5.05–7.02) on slaughtered animals. The estimate of heritability for pH24 was moderate (0.29 ± 0.18). Genetic correlations between pH24 and production or carcass composition traits, except for ultrasonic backfat (UBF), were not significantly different from zero. UBF had a moderate, positive genetic correlation with pH24 (0.24 ± 0.33). These estimates of genetic correlations affirmed that selection for increased growth rate on restricted feeding is likely to result in limited changes in pH24 and pork quality since the selection does not put a high emphasis on reduced fatness.

A community-based wildlife survey: the knowledge and attitudes of residents of suburban Brisbane, with a focus on bandicoots

Within the expanding city of Brisbane in south-east Queensland, numerous fragments of native and regrowth vegetation are scattered across the largely urbanised landscape. These fragments provide refuge to a great diversity of native wildlife, and, provide residents with the opportunity to experience nature on their doorstep. To assess the diversity and abundance of this wildlife, recent changes in these parameters, and the value of wildlife and bushland fragments to residents of Brisbane, a questionnaire survey was distributed to 300 households each located adjacent to one of 38 urban bushland fragments. A total of 172 surveys (57%) were returned, producing 768 records of 83 fauna species, dominated by birds and mammals; bandicoots were widely reported from the 38 fragments. Several historical records provided evidence of recent local extinctions within fragments, highlighting the continuing declines in various species of native wildlife within Brisbane. Several human-wildlife conflicts were identified, but overall residents were tolerant of such conflicts. Bandicoots were disliked by a small minority (3%) of residents owing to the holes they dig in lawns and gardens in search of food. and their potential as vectors of ticks. Most respondents expressed ail appreciation for the presence of native wildlife (96%) and bushland fragments (97%) in their local area, emphasising the importance of incorporating human dimension values into the management of this urban biodiversity.

Public choice of species for the 'Ark': Phylogenetic similarity and preferred wildlife species for survival

Humans play a role in deciding the fate of species in the current extinction wave. Because of the previous Similarity Principle, physical attractiveness and likeability, it has been argued that public choice favours the survival of species that satisfy these criteria at the expense of other species. This paper empirically tests this argument by considering a hypothetical ‘Ark’ situation. Surveys of 204 members of the Australian public inquired whether they are in favour of the survival of each of 24 native mammal, bird and reptile species (prior to and after information provision about each species). The species were ranked by percentage of ‘yes’ votes received. Species composition by taxon in various fractions of the ranking was determined. If the previous Similarity Principle holds, mammals should rank highly and dominate the top fractions of animals saved in the hierarchical list. We find that although mammals would be over-represented in the ‘Ark’, birds and reptiles are unlikely to be excluded when social choice is based on numbers ‘voting’ for the survival of each species. Support for the previous Similarity Principle is apparent particularly after information provision. Public policy implications of this are noted and recommendations are given.

PCR detection and analysis of Pasteurella multocida from the tonsils of slaughtered pigs in Vietnam

A total of 36 tonsil swab samples were collected from healthy swine prior to slaughter at the abattoirs in Can tho and Tien giang provinces of Southern Vietnam, The presence of Pasteurella multocida in these samples was detected by the combination of direct cultivation and isolation, mouse inoculation and the polymerase chain reaction (PM-PCR). P. multocida was detected in 16 samples by PCR, with 17 strains ultimately isolated. All samples were negative for serogroup B by HSB-PCR and conventional serotyping, with isolates identified as A:3, D:1 or D:3. In addition, all samples were determined to be negative for the P. multocida toxin (PMT). Characterisation of isolated P, multocida by REP-PCR and biotyping revealed nine distinct REP profiles and seven biotypes among the 17 isolates. Some correlation was seen with P. multocida isolated from a previous Australian outbreak of acute swine pasteurellosis, and those isolated from fowl cholera outbreaks in Vietnamese poultry. (C) 2000 Elsevier Science B.V. All rights reserved.